Increasingly in law enforcement it is necessary to collect biological samples as evidence of a crime or for use as identifying information of a particular human as is the case of DNA collection from suspects. In the collection of biological specimens, it is necessary to associate information about the subject with the specimen at the time of collection, as there is no manner for identifying a biological specimen by simple inspection. Therefore, a useful form of evidence collection device for use with biological specimens will contain, at least, a suspect information portion for recording subject information data thereon.
The use of biological specimens as evidence further requires that the biological specimen be securely associated with the identifying information so as to assure that after collection of the specimen, the collection paper or absorbent cannot be intentionally or inadvertently switched to a different collection paper. At a minimum, a proper evidence collection device or holder should easily and clearly show that tampering was attempted either by damage to delicate indicia on the device or by overt damage to a strongly secured device. It is further beneficial if the evidence collection device can accommodate additional forms of evidence such as the application and storage of finger prints on the evidence holder.
A particular issue in the collection of the biological sample is that the sample collection is often taken from a living, uncooperative person. Often the sample is to be taken from the mouth of the suspect where a saliva or DNA specimen is needed. In this instance, the collection absorbent used will be attached to a handle or a stick. Once the specimen is on the absorbent, the handle is no longer needed, and presents a complicating factor in specimen storage and analysis due to the extra bulk and size of a handle.
The foregoing issues relate, generally, to a process referred to as evidence “chain of custody.” “Chain of custody” encompasses the procedures and documentation used to maintain and demonstrate the chronological history of the evidence. Documentation should include, for example, name or initials of the individual collecting the evidence, each person or entity subsequently having custody of it, dates the items were collected or transferred, agency and case number, victim's or suspect's name, and a brief description of the item. In biological samples, the principles of evidence or sample identification involved in maintaining proper “chain of custody” are especially critical as a fluid or cellular biological sample, once collected onto an absorbent, presents no distinguishing characteristics. This lack of visual characteristics foils any attempt to properly identify such a biological fluid or cellular sample once it has become separated from its identifying information.
Another problem or issue presented in the analysis of biological specimens is the need to extract or transfer the collected sample from the original collection absorbent and onto an alternate medium to permit analysis or testing of the specimen using the analysis equipment that is available in the selected laboratory. Often it is necessary to separate the collection absorbent from its originally obtained identifying information that is directly associated with the original collection absorbent. This separation of specimen from identifying information can lead to mistakes in associating the specimen with the correct subject or suspect or can lead to the “chain of custody” being open to question in court and a failure of proof of a crime. Sample misidentification is a major source of error both in laboratory analysis and in substantiating criminal evidence.
Importantly, another issue relating to the collection of biological specimens is that biological specimens degrade, hindering or affecting downstream analysis. This is especially true if the collected biological specimen remains wet for extended periods of time, and/or is not treated with stabilizing formulations. Methods of stabilizing biological specimens used in the forensics community have streamlined the collection and extraction of biomolecules from a variety of samples. These methods include transferring a collected specimen from the collection swab to a stabilizing matrix that harbors storage medium, such as chaotropic salts, that slow down the degradation process. However, such stabilizing methods known in the art are associated with problems. In particular, the collected specimen may not transfer to the stabilizing matrix in a consistent or reproducible manner. Further, if the swab used to collect the sample is separate and distinct from the stabilizing matrix receiving the sample, then forensic chain of custody issues arise.
Accordingly, a need still exists for a specimen collection device that is securely associated with the specimen collection absorbent and subject identifying information, while providing ease of use for the collecting user in the field, efficient drying and preservation of the collected specimen, ease of storage, and compatibility with automated analysis equipment. Further, it would be beneficial if such device was tamper proof or tamper evident.